DESCRIPTION: This new application was originally reviewed in October, 1994, at which time it was deferred for additional information. The review was completed in February, 1995. The application proposes to study the impact of liability reforms on insurance companies offering medical malpractice coverage and on litigation outcomes by a retrospective review of two data sets. The first set is compiled from files of the National Association of Insurance Commissioners (NAIC), covering 1984-1991 with information by state on every firm writing medical malpractice insurance. It includes the firm characteristics and their losses on policies they have written in a particular year, their premiums and the resulting loss ratios (firms losses/premiums). The investigators already have done extensive work with the NAIC data, which they propose to extend by changing from the state-year as the unit of analysis to the firm-state-year. Simple descriptive and various regression techniques will be used to look at the impact of liability reform and other firm characteristics on losses and profitability. The other data base is the computer records for the U.S. Federal courts on the 11,000 medical malpractice cases filed and resolved in the period from 1983- 1989. The investigators have built but not yet analyzed the Federal court dataset, and their plans for this data set were not given in detail.